Absorbing means especially for firearms



Q k w w Q E Q3 v A A/ 9 f Nov. 7, 1944.

M. BIRKIGT ABSORBING MEANS ESPECIALLY FOR FIREARMS Filed April 24, 1940 Patented Nov. 7, 1944 ABSORBING MEANS ESPECIALLY FOR FIREARMS Marc Birkigt, Versoix, near Geneva, Switzerland Application April 24, 1940, Serial No. 331,472 I In France October 14, 1939 1 Claim.

The present invention relates to means for preventing or at least partly absorbing injurious reboundings of systems which are to be stopped, at least temporarily, by abutment against a fixed element. The invention is more especially, although not exclusively, concerned, among these means, with those intended to prevent dangerous rebounding of parts or combinations of parts adapted to keep temporarily in active position a system for ensuring the locking of the breech system of an automatic firearm.

The object of the present invention is to provide means of the type above mentioned which are better adapted to' meet the requirements of practice than those used for the same purpose up to the present time.

According to an essential feature of the present invention, I provide, in the system which is to be protected against rebounding, at least one chamber or recess in which is mounted a sliding mass adapted to undergo, under the effect of inertia and against the action of an elastic device, when the system is stopped by abutment, a displacement at the end of which there is produced a shock against the front end of its chamber, said mass being preferably chosen in such manner that its momentum substantially balances the rebounding energy of the system when the shock in question takes place.

Other features of the present invention will result from the following detailed description of some specific embodiments thereof.

A preferred embodiment of the present invention will be hereinafter described, with reference to the accompanying drawing, given merely by way of example, and in which:

Fig. 1 is an elevational view of the breech mechanism of an automatic gun made according to the present invention, with a device for preventing the rebounding of certain parts;

Fig. 2 is a transverse sectional view on the line IIII of Fig. 1;

Fig. 3 is a horizontal sectional view on the line III-III of Fig. 1;

Fig. 4 is an elevational view similar to Fig. 1, showing the breech mechanism in the locked position.

In the following description, I will consider the case of an automatic gun in which the breech system is locked in the firing position thereof. The object of the invention is to provide a device for preventing the detrimental rebounding of the parts which temporarily maintain the breech system locked in active position.

Preferably, the firearm is devised in such manner that, when the breech system is locked, a rigid whole, including a firing pin or the like and safety inclined surfaces, keeps moving toward,

the front, under the effect of a return spring and by inertia and thus fires the cartridge, the safety tion (that is to say the rigid whole above mentioned including the safety inclined surfaces in the case of theautomatic firearm above considered) at least one chamber or recess, L in which is mounted a sliding mass M adapted to undergo, by inertia and against the action of elastic means S, as soon as said whole comes to abut, at the end of its stroke, against a fixed part of the arm, a displacement producing a shock against the front end of chamber L.

In such an arrangement, if, for some reason the cartridge is not fired immediately the firing pin assembly has reached the end of its stroke. that is, when a mlsflre (sometimes called a hangfire) occurs. this assembly rebounds.

But, before the recoil movement of the firing pin assembly has reached the amplitude for which the safety inclined surfaces cease to act, mass M comes to produce, against the front end of its chamber, a shock in the course of which it imparts to said assembly its own momentum which is in a direction opposed to the rebounding force of the firing pin assembly.

Preferably, in this case, the relative masses of said system and of element M will be chosen in such manner that the momentum of said element, when the shock takes place, substantially balances the perturbing rebounding energy.

In this way, the shook of mass M against the front end of its chamber stops the recoil movement of the firing pin assembly and, accordingly, this movement is limited to a small amplitude, for which the safety inclined surfaces are still in a position to maintain the breech system locking device in active position.

I will now proceed to describe more in detail the particular embodiment illustrated by the drawing.

At the rear of barrel I, which is made of any suitable structure, I fix a breech box 2 inside which a breech block can move with a reciprocating movement.

This breech box 2 includes the following elements:

a. On the one hand, a slot 3 for the feed of cartridges; and

b. On the other hand, an aperture 4, which may be diametrally opposed to said slot, for the outlet of the empty shells of the spent cartridges.

I provide, for reciprocating movement in said box 2, a breech block 6.

The breech block 6 carries a firing pin as- .be fired by the firing pin ll.

and it is also mounted for relative reciprocating sliding movement with respect to the breech block 6. A spring 5, eating on the firing pin assembly urge the breech block 6 toward its closing position in which the breech block has pushed the cartridge into the gun chamber and into position for firing.

- I provide the breech block 6 with locking means 1 according to produce the following results, vaccording as said device or means is in the upper or lower position:

a. Either to secure, as long as breech block 6 is behind its firing position, said breech block to the firing pin assembly, by bearing against an inclined surface 8 carried by said firing pin assembly;

1). Or, on the contrary, to lock breech block 6 withmespect to breech box 2 once said breech block has reached its firing position, in which case, the firing pin assembly is free to move 'forward a further distance, owing to the provision of an elongated passage 6' in the breech block 6 for a transverse member I (above mentioned), under the action of recoil spring 5 which bears against said transverse member. The cartridge being held in position by breech block 6, can thus In this position, the safety inclined surfaces above referred to are the rear edges 9" of slide members 9 for keeping the locking means I in the lower position (shown by Fig. 4)

I provide means, such for instance as the combination of a'cylinder l2 and a piston IS, the movable part of which is rigid with a push piece I4, for ensuring, owing to the pressure supplied by a portion of the burnt gases, the recoil movement of slide members 9 until the rear edges 9" thereof cease to act on" the locking means 'I and said slide members come to abut against breech block 6 which is then disengaged from, breech box 2, owing to the reversibility of inclined surface IS on which the locking means I is bearing, said breech block being then pushed rearwardly together with the slide members 9 to which it is then secured through the locking means I.

Advantageously, I interpose between the breech block 6, and the firing pin assembly, an elastic system which tends to push the firing pin assembly toward the front part of the breech block 6, the breech block 6 being supposed to be fixed at this time.

According to a particular embodiment of the invention, I provide respectively in each of the slide members 9 two chambers or recesses L in which are mounted masses M the sliding displacements of which are guided by pistons 31 aeerass whichengage in holes provided for this purpose in said masses. Springs S are provided on the inside of said holes so as to urge the masses rearwardly '(toward the positions of rest illustrated by Figs. 1 and 3).

The strength of these springs will then be chosen in such manner that the masses come to strike the front ends of their chambers when the slide members come to be stopped (position shown by Fig. 4) and that, at the time of the shock, their momentum is suflicient for ensuring the balancing of the rebounding energy.

It should be noted that safety springs I! also oppose, to a certain degree, a. detrimental rebounding of the slide members, but their action is purely of a static nature, and they serve rather to prevent any undesirable backward movement of said slide members under the action of gravity for instance when the gun is vertical, or in case of breaking of the return spring.

The operation of the device according to the invention results sufficiently clearly from the above description for making it unnecessary to enter into further explanations.

In a general manner, while I have, in the above description, disclosed what I deem to be' practical and efficient embodiments of the present invention, it should be well understood that I do not wish to be limited thereto as there might be changes made in the arrangement, disposition and form of the parts without departing from the principle of the present invention as comprehended within the scope of the accompanying claim.

What I claim is:

In an automatic fire arm including a. breech box and a breech block slidabiy mounted in said breech box for movement to and fromfiring position, a firing pin assembly carried by said breech block normally to move therewith, said firing pin assembly including a pair of slide members disposed on the sides of the breech block, said breech block having a transverse opening and said slide members being connected by a transverse bar disposed through said opening, the opening being of greater width than the width of said bar, whereby the firing pin assembly may move forwardly a slight distance to fire a cartridge after the breech block has engaged the cartridge in firing position, a spring acting against the firing pin assembly for urging said assembly and the breech block forwardly, temporary locking means for locking said slide members and said breech block together when the latter is not in its full forward position and for locking the breech block with respect to the breech box when the breech block is in full forward position, said locking means being actuated to its'last named locking position by continued forward movement of said slide members after the breech block has reached the limit of its forward movement, and means for assuring the continued locking of the breech block with respect to the breech box in the event of a hang fire, said means comprising a mass mounted in a chamber in one of said slide members for sliding movement in the direction of forward movement of said breech block, a piston engaging the front end of said chamber and a spring dis- ,posed between the piston and said mass and urging said mass in a rearward direction.

MARC BIRKIGT. 

